FFmpeg
tscc.c
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1 /*
2  * TechSmith Camtasia decoder
3  * Copyright (c) 2004 Konstantin Shishkov
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * TechSmith Camtasia decoder
25  *
26  * Fourcc: TSCC
27  *
28  * Codec is very simple:
29  * it codes picture (picture difference, really)
30  * with algorithm almost identical to Windows RLE8,
31  * only without padding and with greater pixel sizes,
32  * then this coded picture is packed with ZLib
33  *
34  * Supports: BGR8,BGR555,BGR24 - only BGR8 and BGR555 tested
35  */
36 
37 #include <stdio.h>
38 #include <stdlib.h>
39 
40 #include "avcodec.h"
41 #include "internal.h"
42 #include "msrledec.h"
43 
44 #include <zlib.h>
45 
46 typedef struct TsccContext {
47 
50 
51  // Bits per pixel
52  int bpp;
53  // Decompressed data size
54  unsigned int decomp_size;
55  // Decompression buffer
56  unsigned char* decomp_buf;
58  int height;
59  z_stream zstream;
60 
61  uint32_t pal[256];
63 
64 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
65  AVPacket *avpkt)
66 {
67  const uint8_t *buf = avpkt->data;
68  int buf_size = avpkt->size;
69  CamtasiaContext * const c = avctx->priv_data;
70  AVFrame *frame = c->frame;
71  int ret;
72  int palette_has_changed = 0;
73 
74  if (c->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
75  int size;
76  const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, &size);
77 
78  if (pal && size == AVPALETTE_SIZE) {
79  palette_has_changed = 1;
80  memcpy(c->pal, pal, AVPALETTE_SIZE);
81  } else if (pal) {
82  av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
83  }
84  }
85 
86  ret = inflateReset(&c->zstream);
87  if (ret != Z_OK) {
88  av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
89  return AVERROR_UNKNOWN;
90  }
91  c->zstream.next_in = buf;
92  c->zstream.avail_in = buf_size;
93  c->zstream.next_out = c->decomp_buf;
94  c->zstream.avail_out = c->decomp_size;
95  ret = inflate(&c->zstream, Z_FINISH);
96  // Z_DATA_ERROR means empty picture
97  if (ret == Z_DATA_ERROR && !palette_has_changed) {
98  return buf_size;
99  }
100 
101  if ((ret != Z_OK) && (ret != Z_STREAM_END) && (ret != Z_DATA_ERROR)) {
102  av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", ret);
103  return AVERROR_UNKNOWN;
104  }
105 
106  if ((ret = ff_reget_buffer(avctx, frame, 0)) < 0)
107  return ret;
108 
109  if (ret != Z_DATA_ERROR) {
111  c->decomp_size - c->zstream.avail_out);
112  ff_msrle_decode(avctx, frame, c->bpp, &c->gb);
113  }
114 
115  /* make the palette available on the way out */
116  if (c->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
117  frame->palette_has_changed = palette_has_changed;
118  memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
119  }
120 
121  if ((ret = av_frame_ref(data, frame)) < 0)
122  return ret;
123  *got_frame = 1;
124 
125  /* always report that the buffer was completely consumed */
126  return buf_size;
127 }
128 
130 {
131  CamtasiaContext * const c = avctx->priv_data;
132  int zret; // Zlib return code
133 
134  c->avctx = avctx;
135 
136  c->height = avctx->height;
137 
138  // Needed if zlib unused or init aborted before inflateInit
139  memset(&c->zstream, 0, sizeof(z_stream));
140  switch(avctx->bits_per_coded_sample){
141  case 8: avctx->pix_fmt = AV_PIX_FMT_PAL8; break;
142  case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break;
143  case 24:
144  avctx->pix_fmt = AV_PIX_FMT_BGR24;
145  break;
146  case 32: avctx->pix_fmt = AV_PIX_FMT_0RGB32; break;
147  default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample);
148  return AVERROR_PATCHWELCOME;
149  }
150  c->bpp = avctx->bits_per_coded_sample;
151  // buffer size for RLE 'best' case when 2-byte code precedes each pixel and there may be padding after it too
152  c->decomp_size = (((avctx->width * c->bpp + 7) >> 3) + 3 * avctx->width + 2) * avctx->height + 2;
153 
154  /* Allocate decompression buffer */
155  if (c->decomp_size) {
156  if (!(c->decomp_buf = av_malloc(c->decomp_size))) {
157  av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
158  return AVERROR(ENOMEM);
159  }
160  }
161 
162  c->zstream.zalloc = Z_NULL;
163  c->zstream.zfree = Z_NULL;
164  c->zstream.opaque = Z_NULL;
165  zret = inflateInit(&c->zstream);
166  if (zret != Z_OK) {
167  av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
168  return AVERROR_UNKNOWN;
169  }
170 
171  c->frame = av_frame_alloc();
172  if (!c->frame)
173  return AVERROR(ENOMEM);
174 
175  return 0;
176 }
177 
179 {
180  CamtasiaContext * const c = avctx->priv_data;
181 
182  av_freep(&c->decomp_buf);
183  av_frame_free(&c->frame);
184 
185  inflateEnd(&c->zstream);
186 
187  return 0;
188 }
189 
191  .name = "camtasia",
192  .long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Capture Codec"),
193  .type = AVMEDIA_TYPE_VIDEO,
194  .id = AV_CODEC_ID_TSCC,
195  .priv_data_size = sizeof(CamtasiaContext),
196  .init = decode_init,
197  .close = decode_end,
198  .decode = decode_frame,
199  .capabilities = AV_CODEC_CAP_DR1,
200  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
201 };
#define FF_CODEC_CAP_INIT_CLEANUP
The codec allows calling the close function for deallocation even if the init function returned a fai...
Definition: internal.h:48
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
int ff_msrle_decode(AVCodecContext *avctx, AVFrame *pic, int depth, GetByteContext *gb)
Decode stream in MS RLE format into frame.
Definition: msrledec.c:249
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1481
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1778
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:133
unsigned char * decomp_buf
Definition: tscc.c:56
AVCodec.
Definition: avcodec.h:3492
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
z_stream zstream
Definition: tscc.c:59
uint8_t
#define av_cold
Definition: attributes.h:82
#define av_malloc(s)
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:189
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
Definition: frame.c:443
static av_cold int decode_init(AVCodecContext *avctx)
Definition: tscc.c:129
uint8_t * data
Definition: avcodec.h:1480
ptrdiff_t size
Definition: opengl_enc.c:100
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2792
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE bytes worth of palette...
Definition: avcodec.h:1193
uint8_t * av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:350
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Identical in function to ff_get_buffer(), except it reuses the existing buffer if available...
Definition: decode.c:2015
const char * name
Name of the codec implementation.
Definition: avcodec.h:3499
AVCodecContext * avctx
Definition: tscc.c:48
GetByteContext gb
Definition: tscc.c:57
AVCodec ff_tscc_decoder
Definition: tscc.c:190
int width
picture width / height.
Definition: avcodec.h:1741
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
if(ret)
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
Libavcodec external API header.
main external API structure.
Definition: avcodec.h:1568
void * buf
Definition: avisynth_c.h:766
uint32_t pal[256]
Definition: tscc.c:61
static void inflate(uint8_t *dst, const uint8_t *p1, int width, int threshold, const uint8_t *coordinates[], int coord, int maxc)
Definition: vf_neighbor.c:197
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:452
AVFrame * frame
Definition: tscc.c:49
unsigned int decomp_size
Definition: tscc.c:54
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
common internal api header.
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:375
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
void * priv_data
Definition: avcodec.h:1595
static av_cold int decode_end(AVCodecContext *avctx)
Definition: tscc.c:178
int height
Definition: tscc.c:58
#define av_freep(p)
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
This structure stores compressed data.
Definition: avcodec.h:1457
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:984
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: tscc.c:64
#define AV_PIX_FMT_0RGB32
Definition: pixfmt.h:364